Problems

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Total results29,445 problems

Team Contest
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Excursions
Medium5
BFS, Graph+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Ravnica
Medium5
Tree, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Expressions
Medium5
Recursion, String+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Artificial
Medium5
Dynamic programming, Matrix
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Cube
Medium5
Array, Implementation
No attempts yet
Time limit
1.5s
Memory limit
1024 MB
Judgeable
Croats
Medium5
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Marinada
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Pikule
Medium5
Greedy, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sum
Medium5
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Arithmetic or geometric sequence?
Medium5
Array, Hash map+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Pikulice
Medium5
BFS, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
K-TI
Medium5
Simulation, Segment tree+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Training Schedule for ICPC
Medium5
Math, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Matchsticks
Medium5
Implementation, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
SMRAD
Medium5
Dynamic programming, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Predicting the grass
Medium5
BFS, Graph+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Sweet and Salty Pizza
Medium5
Prefix sum, Sliding window+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Poker
Medium5
Dynamic programming, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Strawberries and Tomatoes
Medium5
Matrix, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Zigzag Subarrays
Medium5
Array, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hangman 2
Medium5
Hash map, String+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Broken Communication Towers
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Balloon Darts
Medium5
Union-find, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
86 Eighty-Six 1
Medium5
Dynamic programming, BFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Cat Can Schedule
Medium5
Dynamic programming, Brute force
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Hacker Lee Dong-sik
Medium5
Binary search, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Airplane exhibition
Medium5
Simulation, Greedy+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
The Picky Koala's Way to Eat Eucalyptus Leaves Happily
Medium5
Dynamic programming, Simulation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Seat Shuffle
Medium5
Array, Math+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Power Dwelling in 3
Medium5
Tree, DFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Knock Down Dominoes
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Free Pass
Medium5
Greedy, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Fire Truck
Medium5
Graph, Shortest path+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Carousel
Medium5
Prefix sum, Array+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Tree and Path Count Queries
Medium5
Tree, DFS+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Bracket-and-bar Sequences
Medium5
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Good Node Set Search
Medium5
Tree, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Fast Random Number Search
Medium5
BFS, Dynamic programming+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Fast Random Number Search
Medium5
Dynamic programming, Shortest path+2
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Harvest the most apples from k tree nodes
Medium5
Dynamic programming, Tree+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Wheel String
Medium5
Dynamic programming, Simulation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Meeting Plaza
Medium5
Prefix sum, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ingyeonggang
Medium5
Intervals, Two pointers+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Poker Game: Decision
Medium5
Game theory, Brute force+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Set and Sequence and Query
Medium5
Intervals, Hash map+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Computation: Task 8
Medium5
Bit manipulation, Math+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Computation - Task 9
Medium5
Sorting, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Crossing the Field
Medium5
Dynamic programming, Array
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Barn Construction
Medium5
Stack, Matrix+1
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
RCV Simplification
Medium5
Sorting, Prefix sum+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Panda Hunting Treasure Box
Medium5
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lecture Allocation
Medium5
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate Pyramid
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Splitting Chocolate After One Bite
Medium5
Dynamic programming, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Chocolate and the Friends' Raid
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Tutorial Groupings
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Ultimate Commitment Forever
Medium5
Combinatorics, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Time to Eat
Medium5
BFS, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Palindromic Primes
Medium5
Number theory, Implementation
No attempts yet
Time limit
12s
Memory limit
1024 MB
Judgeable
2D Array Multi-Update Single Sum
Medium5
Prefix sum, Matrix+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Range Add and Range Sum on Time Intervals
Medium5
Segment tree, Implementation
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Food Display Arrangement
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
x
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Hidden Message
Medium5
Dynamic programming, String
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Make the team
Medium5
Graph, Binary search
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Wedding DJ
Medium5
Intervals, Sorting+2
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Gone Fishing
Medium5
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
More or Less
Medium5
Backtracking, Matrix
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Team Shirts/Jerseys
Medium5
Backtracking, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Multimodal Transport
Medium5
Graph, Shortest path+1
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Rotating Cards
Medium5
Greedy, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Jedi and the Galactic Empire
Medium5
Dynamic programming, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lineup the Dominoes
Medium5
Bit manipulation, Dynamic programming
No attempts yet
Time limit
3s
Memory limit
1024 MB
Judgeable
Rising Tides
Medium5
Graph, BFS+2
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Time for Hunting!
Medium5
Brute force, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Choosing the Gateway
Medium5
Bit manipulation, Tree+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lost Edge
Medium5
BFS, Heap+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Lightbulbs
Medium5
Dynamic programming, Probability
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Reach for the Stars
Medium5
Backtracking, Brute force+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Longest Path
Medium5
Graph, Sorting
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Gift Discount
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Islands Tour
Medium5
Graph, DFS+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Temporal Graph
Medium5
Dynamic programming, Graph+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Sunwoo's Setlist
Medium5
Dynamic programming, Math
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Staircase Building (Small)
Medium5
Dynamic programming, Array
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Professor, Please Don't Be Upset
Medium5
Dynamic programming, String
No attempts yet
Time limit
1.5s
Memory limit
512 MB
Judgeable
Hyundai Mobis Autonomous Driving System
Medium5
BFS, Shortest path+1
No attempts yet
Time limit
1s
Memory limit
512 MB
Judgeable
Domino Toppling
Medium5
Stack, Sorting+1
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Harvesting apples and pears from k tree nodes
Medium5
Dynamic programming, Tree
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Harvest the Most Pears Using Only k Apple Nodes
Medium5
Dynamic programming, Tree+1
No attempts yet
Time limit
3s
Memory limit
512 MB
Judgeable
Heavy Hauling
Medium5
Greedy, Sorting+1
No attempts yet
Time limit
3s
Memory limit
2048 MB
Judgeable
Inked Inscriptions
Medium5
Sorting, Array+1
No attempts yet
Time limit
4s
Memory limit
2048 MB
Judgeable
Drilling Showerheads
Medium5
Geometry, Math
No attempts yet
Time limit
1s
Memory limit
2048 MB
Judgeable
Knitting Patterns
Medium5
Dynamic programming, String
No attempts yet
Time limit
3s
Memory limit
2048 MB
Judgeable
Failing Flagship
Medium5
String, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Kiosk Installation
Medium5
Graph, BFS+1
No attempts yet
Time limit
8s
Memory limit
1024 MB
Judgeable
Leaves at the Academy
Medium5
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
1024 MB
Judgeable
Congested Commute Grid
Medium5
BFS, Matrix+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Hardcore Hangman
Medium5
Bit manipulation, Implementation
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Team ContestGiven N programmers with skill levels from 1 to 10, find the maximum number of disjoint triples whose minimum plus maximum skill exceeds K.	Medium5	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
ExcursionsGiven a grid of nice and ugly cells, answer Q queries with the shortest 4-directional path between two cells that avoids ugly cells, or -1 if none exists.	Medium5	BFSGraph+1	No attempts yet	3s	1024 MB	Judgeable
RavnicaGiven a tree of N cities, find the fewest roads to remove so that every city has at most two roads left.	Medium5	TreeDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
ExpressionsGiven a digit string of up to 15 digits, insert each of +, -, and * at most once between digits and count the distinct non-negative results.	Medium5	RecursionString+2	No attempts yet	1s	1024 MB	Judgeable
ArtificialGiven an N x N table of numbers, answer M queries with the maximum over the square submatrix whose rows and columns both lie in [L, R].	Medium5	Dynamic programmingMatrix	No attempts yet	1.5s	1024 MB	Judgeable
CubeGiven point recolorings in an N x N x N cube, print the first colored cube seen along each ray after rotating a chosen face to the front.	Medium5	ArrayImplementation	No attempts yet	1.5s	1024 MB	Judgeable
CroatsEach known Croat makes all of their descendants Croats, so after each new tip the task asks for the total number of people who are certainly Croats.	Medium5	TreeDFS+1	No attempts yet	1s	1024 MB	Judgeable
MarinadaFind the fewest steps from the entrance to the exit of a grid maze while passing through all K ingredient cells.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	2s	1024 MB	Judgeable
PikuleGiven N integers, find the largest value the last pikule can keep after N-1 pushes, and print a push order that reaches it.	Medium5	GreedyMath+1	No attempts yet	1s	1024 MB	Judgeable
SumGiven digit counts X and Y and a sum Z, count the unordered pairs of integers A and B with X and Y digits that add up to Z.	Medium5	Dynamic programmingMath	No attempts yet	1s	1024 MB	Judgeable
Arithmetic or geometric sequence?After each point update to an array of N values, report whether it is a positive arithmetic sequence (+), a positive geometric sequence (*), or neither (?).	Medium5	ArrayHash map+2	No attempts yet	2s	1024 MB	Judgeable
PikuliceFind the minimum number of slide and jump moves that turn a row of red and blue marbles with one empty stand into all reds, then the empty stand, then all blues.	Medium5	BFSGraph+1	No attempts yet	1s	1024 MB	Judgeable
K-TIGiven a sequence and K, repeatedly remove the largest value at positions divisible by K (first one on ties) and print the removed values in order.	Medium5	SimulationSegment tree+1	No attempts yet	2s	1024 MB	Judgeable
Training Schedule for ICPCArrange n training and m rest days to maximize total power, where a run of k consecutive training or rest days adds or subtracts k squared.	Medium5	MathBrute force	No attempts yet	1s	1024 MB	Judgeable
MatchsticksCount the rectangles whose four sides are fully covered by matchsticks in an N by M grid where corners sit on odd rows and columns.	Medium5	ImplementationPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
SMRADGiven banknote values and a growing set of smelly values, for each query, decide whether amount X can be paid exactly using only non-smelly notes.	Medium5	Dynamic programmingImplementation	No attempts yet	1s	1024 MB	Judgeable
Predicting the grassGiven the current and predicted grass grids and a spread range D, decide whether grass can spread from the current cells to exactly the predicted cells.	Medium5	BFSGraph+1	No attempts yet	2s	1024 MB	Judgeable
Sweet and Salty PizzaOn a circular pizza, odd and even slices get global additions over time. After each query, find the start of the best K-slice window and its sum.	Medium5	Prefix sumSliding window+1	No attempts yet	1s	1024 MB	Judgeable
PokerGiven N distinct cards, find the highest score from forming pairs, triples, four-of-a-kind, and flushes, with each card used at most once.	Medium5	Dynamic programmingBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Strawberries and TomatoesGiven a grid of seed cells, find every cell where a strawberry run and a tomato run of K consecutive cells on a row or column both cover it.	Medium5	MatrixPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Zigzag SubarraysFor each test case, count the contiguous subarrays of length at least 2 whose adjacent elements strictly alternate between rising and falling.	Medium5	ArrayDynamic programming	No attempts yet	1s	512 MB	Judgeable
Hangman 2Given N distinct words of equal length, find each word that can be reached from another word by changing at most two letters.	Medium5	Hash mapString+1	No attempts yet	2s	1024 MB	Judgeable
Broken Communication TowersGiven two tower identifiers a and b, find the minimum-cost divisor-relation path between them, breaking ties by the smallest sum of identifiers on the path.	Medium5	Shortest pathGraph+1	No attempts yet	1s	512 MB	Judgeable
Balloon DartsGiven balloon scores and a burst order, find the highest segment score recorded at any point while the balloons are burst.	Medium5	Union-findImplementation	No attempts yet	1s	512 MB	Judgeable
86 Eighty-Six 1Given Legion positions on an N by N grid, find the minimum diagonal-move time for Shinei to reach every Legion, or report that it is impossible.	Medium5	Dynamic programmingBFS+1	No attempts yet	1s	1024 MB	Judgeable
Cat Can ScheduleGiven N kinds of cans with limited counts, assign one can to each cat on each of K days to maximize the total satisfaction of both cats.	Medium5	Dynamic programmingBrute force	No attempts yet	1s	512 MB	Judgeable
Hacker Lee Dong-sikFind the smallest possible maximum cost among accepted requests, so that every K consecutive requests includes at least one accepted request.	Medium5	Binary searchDynamic programming+1	No attempts yet	1s	512 MB	Judgeable
Airplane exhibitionSimulate one truck that carries split-able parts between two airplanes, and print each part's departure and arrival time.	Medium5	SimulationGreedy+1	No attempts yet	1s	512 MB	Judgeable
The Picky Koala's Way to Eat Eucalyptus Leaves HappilyChoose at most one leaf per day over M days, keeping poison at or below A with B detoxified nightly, to maximize total happiness.	Medium5	Dynamic programmingSimulation	No attempts yet	1s	512 MB	Judgeable
Seat ShuffleGiven a permutation A and a huge day count M (up to 200000 digits), print each member's seat after applying the rule M times.	Medium5	ArrayMath+1	No attempts yet	3s	1024 MB	Judgeable
Power Dwelling in 3Split a tree of N stations into N/3 connected groups of three stations each, or report that no such split exists.	Medium5	TreeDFS+1	No attempts yet	2s	1024 MB	Judgeable
Knock Down DominoesGiven N domino weights, find the largest number of dominoes you can keep in order so that each one weighs no more than the total of all kept dominoes before it.	Medium5	Dynamic programmingArray	No attempts yet	1s	512 MB	Judgeable
Free PassGiven a usage limit for each ride type, find the maximum number of rides you can take without riding the same ride twice in a row.	Medium5	GreedyMath	No attempts yet	1s	512 MB	Judgeable
Fire TruckFind the shortest distance from station S to fire site T, and among all shortest paths, the most water the truck can have on arrival at T.	Medium5	GraphShortest path+1	No attempts yet	2s	512 MB	Judgeable
CarouselGiven N horses on a circle with a_i people on horse i, find the minimum number of moves to adjacent horses so every horse ends with exactly one person.	Medium5	Prefix sumArray+1	No attempts yet	1s	512 MB	Judgeable
Tree and Path Count QueriesGiven a tree with red and blue vertices, count for each query vertex u the red-blue simple paths that have u strictly inside them.	Medium5	TreeDFS+1	No attempts yet	1s	512 MB	Judgeable
Bracket-and-bar SequencesDefine a bijection between regular bracket-and-bar sequences of a given length and integers, then implement it in both directions.	Medium5	CombinatoricsDynamic programming+1	No attempts yet	2s	1024 MB	Judgeable
Good Node Set SearchPick nodes of a tree so that no two are adjacent and every unpicked internal node has a picked child, maximizing the total value.	Medium5	TreeDynamic programming	No attempts yet	1s	512 MB	Judgeable
Fast Random Number SearchFind the fewest moves on a 5 by 5 grid, avoiding -1 cells, to visit the cells labeled 1 through 6 starting from a given cell.	Medium5	BFSDynamic programming+1	No attempts yet	3s	512 MB	Judgeable
Fast Random Number SearchFind the fewest walk or run moves from the start cell needed to visit every cell numbered 1 through 6 in any order on a 5 x 5 board.	Medium5	Dynamic programmingShortest path+2	No attempts yet	3s	512 MB	Judgeable
Harvest the most apples from k tree nodesFind the most apples you can collect by choosing a connected set of at most k nodes that includes root 0.	Medium5	Dynamic programmingTree+1	No attempts yet	3s	512 MB	Judgeable
Wheel StringGiven a cyclic wheel of lowercase letters, find the fewest turns needed to build string S by appending letters, or report -1 if impossible.	Medium5	Dynamic programmingSimulation	No attempts yet	1s	1024 MB	Judgeable
Meeting PlazaGiven an N by M grid of values, pick two rows and two columns to form four paths and find the maximum of the enclosed green cell count plus the sum of the path cells.	Medium5	Prefix sumBrute force	No attempts yet	1s	1024 MB	Judgeable
IngyeonggangGiven each column's water cells in a compressed form, decide whether water can flow from column 1 to column M moving up, down, or right.	Medium5	IntervalsTwo pointers+1	No attempts yet	2s	1024 MB	Judgeable
Poker Game: DecisionAlice and Bob alternately take three of the six community cards each, playing optimally, and the task is to find who ends with the higher hand or a draw.	Medium5	Game theoryBrute force+1	No attempts yet	8s	1024 MB	Judgeable
Set and Sequence and QueryMaintain the count of distinct continuous increasing sequences in a set of integers under insertions and deletions, printing the count after each move.	Medium5	IntervalsHash map+1	No attempts yet	2s	1024 MB	Judgeable
Computation: Task 8Given a real a with \|a\| up to 1e9 and at most 9 decimal digits, output a/10 using only the listed machine instructions.	Medium5	Bit manipulationMath+1	No attempts yet	1s	1024 MB	Judgeable
Computation - Task 9Write an instruction sequence in this restricted language that reads 16 reals and prints them in ascending order.	Medium5	SortingImplementation	No attempts yet	1s	1024 MB	Judgeable
Crossing the FieldPick a subsequence of flowers to maximize the sum of squared differences between adjacent picked beauty values.	Medium5	Dynamic programmingArray	No attempts yet	1s	512 MB	Judgeable
Barn ConstructionGiven a grid with obstacles, the task is to answer for each query (a, b) whether an empty rectangle of a rows and b columns exists.	Medium5	StackMatrix+1	No attempts yet	1.5s	512 MB	Judgeable
RCV SimplificationGiven each candidate's first-choice vote count in a ranked-choice election, find the candidates who cannot win under any possible second-choice ordering.	Medium5	SortingPrefix sum+2	No attempts yet	1s	1024 MB	Judgeable
Panda Hunting Treasure BoxFind the largest treasure box value Panda can reach with his starting energy, where entering a box cell ends the walk.	Medium5	Shortest pathGraph+1	No attempts yet	1s	1024 MB	Judgeable
Lecture AllocationChoose how many lectures (0 to 3) each teacher gives so that exactly L lectures are covered at the lowest total cost.	Medium5	Dynamic programming	No attempts yet	1s	1024 MB	Judgeable
Chocolate PyramidGiven an R x C base, count the white and dark chocolates needed to build the full pyramid, layer by layer, until the top face is empty.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Splitting Chocolate After One BiteCount the domino tilings of a 3 by N block with one cell removed, answering up to 1e5 queries modulo 1e9+7.	Medium5	Dynamic programmingBit manipulation+1	No attempts yet	1s	1024 MB	Judgeable
Chocolate and the Friends' RaidGiven an M x N chocolate with up to 4 eaten squares, find the maximum number of 1x2 or 2x1 pieces that can be cut from the rest.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Tutorial GroupingsCount the ways to split students by knowledge level into ordered groups with level span at most k and size at most s, modulo 1e9+7.	Medium5	Dynamic programmingSorting+1	No attempts yet	1s	1024 MB	Judgeable
Ultimate Commitment ForeverFor each trip, count the shortest grid paths from start to end that avoid up to 10 construction points, modulo 10^9+7.	Medium5	CombinatoricsDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Time to EatFind the shortest grid path from the top-left to the bottom-right cell that enters a sub shop at least once every F steps.	Medium5	BFSShortest path+1	No attempts yet	1s	1024 MB	Judgeable
Palindromic PrimesCount the palindromic primes in the inclusive range from L to H, where L and H are at most 10^12.	Medium5	Number theoryImplementation	No attempts yet	12s	1024 MB	Judgeable
2D Array Multi-Update Single SumGiven an n by n grid and a list of rectangle add and rectangle sum queries, print the one final rectangle sum after all updates are applied.	Medium5	Prefix sumMatrix+1	No attempts yet	3s	512 MB	Judgeable
Range Add and Range Sum on Time IntervalsProcess n queries on one-second slots of a day: add 1 to a time range, or print the sum of values over a time range.	Medium5	Segment treeImplementation	No attempts yet	1s	512 MB	Judgeable
Food Display ArrangementGiven a row of food type IDs, find the fewest types to move to the ends so that every remaining type forms one contiguous block.	Medium5	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
xGiven a vertical cylinder and aircraft flying straight lines with descent, find the times each aircraft enters and exits the cylinder, if it does.	Medium5	GeometryMath	No attempts yet	1s	1024 MB	Judgeable
Hidden MessageCount the ways to split the original phrase into three subsequences that spell the given sub-phrases, modulo 1,000,000,007.	Medium5	Dynamic programmingString	No attempts yet	1s	1024 MB	Judgeable
Make the teamAssign each video a distinct whole-hour start time so that the latest finish time is as early as possible.	Medium5	GraphBinary search	No attempts yet	1s	1024 MB	Judgeable
Wedding DJGiven song fun levels, find the fewest 'change all songs of level x to level y' operations that make the playlist's fun levels never decrease.	Medium5	IntervalsSorting+2	No attempts yet	1s	1024 MB	Judgeable
Gone FishingGiven a net of radius R and n fish positions, find the most fish that fit inside a single circle of radius R.	Medium5	GeometryBrute force	No attempts yet	1s	1024 MB	Judgeable
More or LessFill the blank cells of an n by n Futoshiki grid (n at most 7) so each row and column holds 1 to n once and every less-than or greater-than sign holds.	Medium5	BacktrackingMatrix	No attempts yet	3s	1024 MB	Judgeable
Team Shirts/JerseysGiven friends' jersey numbers and a target t, decide whether Travis can add one number from 1 to 99 so that concatenating some of the numbers gives exactly t.	Medium5	BacktrackingDynamic programming+1	No attempts yet	1s	1024 MB	Judgeable
Multimodal TransportGiven per-mode route costs and a switching cost at each city, find the cheapest cost to ship a package from origin o to destination d.	Medium5	GraphShortest path+1	No attempts yet	3s	1024 MB	Judgeable
Rotating CardsGiven a stack of n shuffled cards, find the minimum total label cost of rotating cards so that cards 1 through n can be discarded in order.	Medium5	GreedyPrefix sum+1	No attempts yet	1s	1024 MB	Judgeable
Jedi and the Galactic EmpireFind the fewest blaster shots that get past one or two Jedi, given the shot times and each Jedi's reaction time between blocks.	Medium5	Dynamic programmingSorting+1	No attempts yet	1s	1024 MB	Judgeable
Lineup the DominoesCount the left-to-right orderings of n flippable dominoes where touching halves match, modulo 1e9+7, for up to 100 sets.	Medium5	Bit manipulationDynamic programming	No attempts yet	3s	1024 MB	Judgeable
Rising TidesFind the path from the top-left to the bottom-right cell of a grid that maximizes the smallest remaining ceiling height as the water rises 1 per second.	Medium5	GraphBFS+2	No attempts yet	2s	1024 MB	Judgeable
Time for Hunting!Choose at most one armor per kind within gold T, with one optional upgrade costing K, to maximize the total attack bonus of five skills.	Medium5	Brute forceImplementation	No attempts yet	1s	1024 MB	Judgeable
Choosing the GatewayGiven a tree whose links carry XOR values, find the gateway node that minimizes the total count of 1 bits in the header received by all nodes.	Medium5	Bit manipulationTree+1	No attempts yet	1s	1024 MB	Judgeable
Lost EdgeGiven a grid of walls and monsters, the task is to decide whether the player can reach the target level by hunting weaker monsters and then reach the raid cell.	Medium5	BFSHeap+1	No attempts yet	1s	1024 MB	Judgeable
LightbulbsGiven an N by M grid where each bulb works with probability P, find the expected length of the longest horizontal run of working bulbs.	Medium5	Dynamic programmingProbability	No attempts yet	1s	256 MB	Judgeable
Reach for the StarsGiven a black and white grid, find the fewest star stamps needed to produce the picture exactly, or report that it is impossible.	Medium5	BacktrackingBrute force+1	No attempts yet	1s	1024 MB	Judgeable
Longest PathGiven a directed graph where every pair of vertices has exactly one edge, find a path that visits every vertex exactly once.	Medium5	GraphSorting	No attempts yet	2s	1024 MB	Judgeable
Gift DiscountGiven n gift prices, a budget b, and up to a half-price discounts, find the most gifts you can buy within the budget.	Medium5	GreedySorting+1	No attempts yet	1s	1024 MB	Judgeable
Islands TourIn a directed graph where each island has at most one outgoing zip-line, find the most distinct islands a tour starting anywhere can visit.	Medium5	GraphDFS+1	No attempts yet	1s	1024 MB	Judgeable
Temporal GraphFind the length of the shortest path from s to e in a temporal graph, where the chosen edges must have strictly increasing time labels.	Medium5	Dynamic programmingGraph+1	No attempts yet	1s	1024 MB	Judgeable
Sunwoo's SetlistCount the ordered song sequences, with repeats allowed, whose running times sum to exactly N minutes, modulo 1,000,000,007.	Medium5	Dynamic programmingMath	No attempts yet	1s	512 MB	Judgeable
Staircase Building (Small)Given column heights, find the fewest blocks to move so that adjacent columns differ by at most 1 in height while the total block count stays the same.	Medium5	Dynamic programmingArray	No attempts yet	2s	512 MB	Judgeable
Professor, Please Don't Be UpsetGiven known words and a misspelled word, find the known word with the lowest alignment score, where each gap costs 1600 and key distances are squared.	Medium5	Dynamic programmingString	No attempts yet	1.5s	512 MB	Judgeable
Hyundai Mobis Autonomous Driving SystemFind the shortest path from the top-left to the bottom-right of a grid that visits at least one waypoint, using up to K uses of a 5x5 jump pattern.	Medium5	BFSShortest path+1	No attempts yet	1s	512 MB	Judgeable
Domino TopplingGiven N dominoes with positions a_i and lengths l_i, count the minimum number that must be pushed by hand so every domino falls in a chain.	Medium5	StackSorting+1	No attempts yet	1s	1024 MB	Judgeable
Harvesting apples and pears from k tree nodesPick a connected set of at most k nodes containing root 0 to maximize apples times pears, then print the apple and pear counts.	Medium5	Dynamic programmingTree	No attempts yet	3s	512 MB	Judgeable
Harvest the Most Pears Using Only k Apple NodesPick a connected subtree containing root 0 that visits at most k apple nodes, maximizing the number of pear nodes harvested.	Medium5	Dynamic programmingTree+1	No attempts yet	3s	512 MB	Judgeable
Heavy HaulingGiven sorted box positions, move the boxes so that no two share a cell while minimizing the sum of squared moving distances.	Medium5	GreedySorting+1	No attempts yet	3s	2048 MB	Judgeable
Inked InscriptionsGiven a permutation, output an order to copy each psalm from old page i to new page p_i using at most 2n*sqrt(n) total page flips.	Medium5	SortingArray+1	No attempts yet	4s	2048 MB	Judgeable
Drilling ShowerheadsGiven concentric circles and a minimum distance e, find the most points that can be placed on them with all pairwise distances at least e.	Medium5	GeometryMath	No attempts yet	1s	2048 MB	Judgeable
Knitting PatternsFor each wool colour, find the minimum total cost of knitting a pattern, counting stitches used, stitches stranded, and each start or end of a colour.	Medium5	Dynamic programmingString	No attempts yet	3s	2048 MB	Judgeable
Failing FlagshipGiven two wind direction strings of up to 1000 letters each, find the smallest turn in degrees that rotates the first direction onto the second.	Medium5	StringImplementation	No attempts yet	1s	1024 MB	Judgeable
Kiosk InstallationFind a plot for the kiosk that every other plot can reach under the greedy walk rule, and report the longest walk, or print impossible.	Medium5	GraphBFS+1	No attempts yet	8s	1024 MB	Judgeable
Leaves at the AcademyGiven an N by N grid, find the fewest adjacent switch pairs to press so the bulb's switch is identified in every case.	Medium5	MathImplementation	No attempts yet	1s	1024 MB	Judgeable
Congested Commute GridFind the fewest moves from (1, 1) to (N, M) on a grid that avoids every cell within Manhattan distance D of a congestion zone, or report NO.	Medium5	BFSMatrix+1	No attempts yet	2s	1024 MB	Judgeable
Hardcore HangmanFind a hidden lowercase string in at most 7 guesses, where each guess reveals every position whose letter is in the guessed set.	Medium5	Bit manipulationImplementation	No attempts yet	2s	1024 MB	Judgeable